Studies will be continued on several aspects of the regulation of glycogen synthase by covalent phosphorylation-dephosphorylation. A calmodulin-dependent synthase kinase is being purified from rabbit liver and characterized in terms of physical, kinetic and regulatory properties. The phosphorylation of glycogen synthase in rabbits in response to hormones will also be determined. The synthase will be purified from hormonally-treated rabbits and characterized with respect to kinetic properties and phosphate content. The phosphorylation sites in purified synthase which has been phosphorylated using various kinses will be studied. The 32P-synthase will be enzymatically degraded and 32P-peptides separated by high performance liquid chromatography.